IL29102A - N-(3-chloro-4-trifluoromethylphenyl)-propionamide,its manufacture and herbicidal compositions containing it - Google Patents

Description

H-( 3-Chldro~4-trifluoromethylpftenyl)*propionamide , its manufacture and herbicidal compositions containing it.

PARBENFABRIKEN BAYER AKTIENGESELLSCBAFT Ci 27566 The present invention relates to a new . carboxylic acid anilide to. a process for its preparation, and to its use as a herbicide.

It is known that N-(3-trifluoromethyl-4-chloro-phenyl)-pro-pionamide can be used as herbicidal active compound (cf. Belgian Patent Specification No. 650 181).

The present invention provides a new carboxylic acid anilide of the formula This new carboxylic acid anilide can be prepared in different ways. It is obtained in particularly simple and advantageous manner when 3-chloro-4-trifluoromethyl-aniline of the formula 01 is reacted (a) with propionic anhydride, optionally in the presence of a diluent, or (b) with a propionyl halide in the presence of an acid binder and in the presence of a diluent, or (c) with propionic acid in the presence of a diluent.

Surprisingly, the new active compound of the invention, has a much greater herbicidal potency than the active compound known previously. The latter is the chemically most proximate active compound of the same type of activity and it is very surprising that the new compound is much better than it. The carboxylic acid anilide of the invention represents a considerable enrichment of the art.

The reaction according to process (a) may be represented by 0 (III) When carrying out the process according to (a), there is used as diluent either a substantial excess of the propionic anhydride or, al ernatively, an inert organic solvent such as benzene, toluene or xylene.

The reaction temperatures can be varied within a fairly wide range; in general, the work is carried out at from 50 to 150°C.

The working up of the reaction mixture may be effected in the usual manner, for example by evaporation of the volatile constituents.

When carrying out the process according to (b), propionyl chloride is preferably used. As diluent, an aliphatic or aromatic inert solvent, such as benzine, benzene or toluene, is suitable. The usual acid binders may be used, that is, alkali metal hydroxides, such as sodium hydroxide and potassium hydroxide, alkali metal carbonates, such as sodium carbonate and potassium carbonate, as well as organic tertiary bases, such as pyridine, dimethyl-aniline, hexahydrodimethylaniline and trie~thylamine .

The reaction temperatures can be varied within a fairly wide range; in general, they are from 50 to 150°C.

The working up of the reaction mixture is effected in the usual manner, for example by washing out with water the salts which are formed, and evaporating the organic solution obtained.

When carrying out the process according to (c) it is desirable that the water formed during the reaction be continuously removed. This can be done easily when a diluent is used which formsan azeotropic mixture with the water and when the azeotropic mixture is distilled off continuously as it is formed.

As diluent, benzene, toluene or xylene is particularly suit The reaction is expediently carried out at boiling tempera- ^ tures of the reaction mixture, normally such temperatures are within the range from 80 to 130°C.

The w orking up of the reaction mixture may take place in cus-toniary manner, for example b evaporation of the volatile constituents.

The new carboxylic acid anilide exhibits strong herbicidal properties and can therefore be used for the control of weeds.

The term "weeds" is used herein in the widest sense to mean all plants which grow in places where they are not desired. Whether the active compound according to the invention acts as total or selective herbicide depends chiefly on the amount used.

The active compound according to the invention can be used for example in the case of the following plants: dicotyledons, such as mustard (Sinapis) , cress (Lepidium) , cleaver (Galium), common chickweed (Stellaria), camomile (Matricaria), smallflower Galinsoga (Galinsoga), fathen (Chenopodium) , stinging nettle (Urtica), groundsel (Senecio), cotton (Gossypium), beets (Beta), carrots (Daucus), beans (Phaseolus), potatoes (Solanum), coffee (Coffea); monocotyledons, such as timothy (Phleum) , bluegrass (Poa), fescue (Festuca), goosegrass (Eleusine), foxtail (Setaria), ryegrass (Lolium) , cheat (Bromus), barnyard grass (Echinochloa), maize (Zea), rice (Oryza), oats (Avena) , barley (Hordeum), wheat (Triticum), millet (Panicum), sugar-cane (Saccharum).

The active compound of the invention can be converted into the usual formulations, such as solutions, emulsions, suspensions, powders, pastes and granulates. These may be produced in known manner, for example by mixing the active compound with extenders, that is, liquid or solid diluents or carriers, optionally with the use of surface-active agents, that is, emulsifying agents and/or dispersing agents. In the case of the use of water as an extender, organic solvents can, for example, also be used as auxiliary solvents.

As liquid diluents or carriers, there are preferably usee aromatic hydrocarbons, such as xylenes or benzene, chlorinated aromatic hydrocarbons, such as chlorobenzenes, paraffins, such mineral oil fractions, alcohols, such as methanol or butanol, or strongly polar solvents, such as dimethyl formamide or dimethyl sulphoxide, as well as water.

As solid diluents or carriers, there are preferably used ground natural minerals, such as kaolins, clays, talc or chalk, or ground synthetic minerals, such as highly-dispersed silicic acid or silicates.

Preferred examples of emulsifying agents include non-ionic and anionic emulsifiers, such as polyoxyethylene-fatty acid esters, polyoxyethylene-fatty alcohol ethers, for example alkylarylpoly-glycol ethers, alkyl sulphonates and aryl sulphonates; and preferred examples of dispersing agents include lignin, sulphite waste liquors and methyl cellulose.

The active compound of the invention may be present in the formulations in admixture with other active compounds.

The formulations contain, in general, from 0.1 to 95» preferably from 0.5 to 90, per cent by weight of active compound.

The active compound of the invention may be used as such, or in the form of its formulations or of the application forms prepared therefrom, such as ready-to-use solutions, emulsions, sus-pensions, powders, pastes and granulates. Application may be effected in the usual manner, for example by spraying, squirting, scattering, dusting or watering.

The active compound may be used in both the pre-emergence process and the post-emergence process. It is particularly expedient that the weeds be controlled in the early stage of development.

The concentration of active compound to be used for actual application may vary within fairly wide ranges; in general, are from 0,005 to 0.5 per cent by weight.

The invention also provides a herbicidal composition containing as active ingredient the compound of formula (I) in admixture with a solid diluent or carrier or in admixture with a liquid diluent or carrier containing a surface-active agent.

The invention also provides a method of combating weeds which comprises applying to the weeds or a weed habitat the compound of formula (I) alone or in the form of a composition containing as active ingredient the compound of formula (I) in admixture with a solid or liquid diluent or carrier.

The herbicidal activity of the new active compound is illustrated by the following Example A.

Example A Post-emergence test Solvent: 5 parts by weight acetone Emulsifier: 1 part by weight alkylaryl polygl col ether To produce a suitable preparation of the active compound, 1 part by weight of the active compound is mixed with the stated amount of solvent, the stated amount of emulsifier is added and the concentrate is then diluted with water to the desired concentration.

Test plants which have a height of about 5-15 cm. are sprayed with the preparation of the active compound until just dew moist. After three weeks, the degree of damage to the plants is determined and characterised by the values 0-5, which have the following meaning: 0 no effect 1 a few slightly burnt spots 2 marked damage to leaves 3 some leaves and parts of stalks partially dead 4 plant partially destroyed plant completely dead.

The active compounds, their concentrations and the r»s--¾i obtained can be seen from the following Table: T A B L E Post - emergence test Active compound Concentration Echino- Sinapis Gali VJ1 of active chloa O compound j» -J The process of the invention is illustrated by the following Example 1.

Example 1 To 29.7 of 3-chloro-4-trifluoromethylaniline in 100 ml of toluene there are added dropwise, in 5 minutes and at 50°C, 22 ml (l.l equivalents) o propionic anhydride. The temperature rises from 50°C to 60°C. Heating to 90-100°C is then effected for 2 hours and propionic acid and toluene are then distilled off in a vacuum. The crystalline residue is recrystallised from cyclo-hexane and the colourless crystals are washed with petroleum ether, m.p. 95-97°C Yield: 30g of N-(3-chloro-4-trifluoromethyl-phenyl)-propionamide (propionic acid 3-chloro-4-trifluoromethyl anilide).

Claims (1)

1. HAVING NOW particularly described and ascertained nature of our said invention and in what manner the same is performed, we declare, that what we claim is: WHAT WE CLAIM IS: 1 · The anilide of the formula 2. A process for the production of the anilide according to claim 1 in which 3-chloro-4-trifluoromethyl-aniline of the formula is reacted (a) with propionic anhydride, optionally in the presence of a diluent, or (b) with a propionyl halide in the presence of an acid binder and in the presence of a diluent, or (c) with propionic acid in the presence of a diluent. 3. A process according to claim 2 (a) in which a substantial excess of the propionic ajihydride or an organic solvent is used as the diluent. 4. A process according to claim 2 (a) or 3 in which the reaction is effected at 50 to 150°C. 5. A process according to claim 2(b) in which the propionyl halide is propionyl chloride. 6. A process according to claim 2 (b) or 5 in which the diluent is an aliphatic or aromatic solvent. 7. A process according to claim 2 (b), 5 or 6 in which the reaction is effected at 50 to 150°C. 8. A process according to claim 2 (c) in which a diluent is used which forms an azeotropic mixture with water formed r during the reaction and the azeotropic mixture is distilled off continuously as it is formed* 9· A process according to claim 8 in which the diluent is benzene, toluene or xylene. 10. A process according to claim 2 (c), 8 or 9 in which the reaction is effected at boiling temperature of the reaction mixture. 11. A process for the production of an anilide according to claim 1 substantially as hereinbefore described in Example 1 · 12. An anilide according to claim 1 whenever prepared by a process according to any of claims 2 - 11. 1 · A herbicidal composition containing as active ingredient the compound according to claim 1 or 12 in admixture with a solid diluent or carrier or in admixture with a liquid diluent or carrier containing a surface-active agent. 14. A composition according to claim 13 containing from 0.1 to 95 of the active compound, by weight. 15· A method of combating weeds which comprises applying to the weeds or a weed habitat the compound according to claim 1 or 12 alone or in the form of a composition containing as active ingredient the compound according to claim 1 or 12 in admixture with a solid or liquid diluent or carrier. 16* A method according to claim 15 in which a composition is used containing from 0.005 to 0.5 of the active compound, by weight, 17· A method according to claim 15 or 16 in which the weeds are any of those hereinbefore mentioned. Dated this 10th day of December, 1967 For the Applicants P]ARTNERS